Thin-film transistor, array substrate, display panel and display device

ABSTRACT

Embodiments of the disclosure provide a thin-film transistor, an array substrate, a display panel and a display device. The thin-film transistor includes a current enhancement portion, and the current enhancement portion is provided between a drain and a source. The current enhancement portion may include at least one protrusion portion, and the protrusion portion is provided on the drain and/or the source and faces a channel. The current enhancement portion may include an island portion provided between the drain and the source, and the island portion is separate from the drain and the source. The island portion may include at least one protrusion end, and the at least one protrusion end faces the drain and/or the source.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a U.S. National Stage under 35 U.S.C. § 371of International Application No. PCT/CN2017/083043, filed on May 4,2017, which claims priority to and the benefit of Chinese ApplicationNo. 201620510831.8 filed on May 31, 2016 and entitled “THIN-FILMTRANSISTOR, ARRAY SUBSTRATE, DISPLAY PANEL AND DISPLAY DEVICE”, thedisclosure of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The disclosure relates to a thin-film transistor, an array substrate, adisplay panel and a display device.

BACKGROUND

With progress in technology, a consumer has increasingly higherrequirements for a display electronic product. For example: finer imagesor narrower frames, and the like. Certainly, finer images or narrowerframes, and the like, all require smaller circuit components orstructural units.

For example, finer images requires smaller pixel units. In a case wherethe circuit structures of the pixel units are the same, the reduction inthe area of the pixel units will cause a reduction in the aperture ratioof the pixels. In this case, in order to guarantee the brightness of thepicture unchanged, it is necessary to increase the brightness of theback lighting, thereby causing increase in power consumption of thedisplay panel.

In the related art, an attempt to optimize circuit components orstructures in the pixel units has been made, in order to reduce the areaof the opaque region and improve the aperture ratio. It is difficult forthis method to be effective to the pixel units which have been verysmall. How to improve the aperture ratio of the pixel on smaller pixelunits is a problem which is faced for now and will be faced in thefuture.

On the other hand, for the anti-electrostatic circuit in the peripheralregion of the display panel, it is also necessary to optimize circuitcomponents or structure units to reduce the occupied area and meet therequirement for narrow frames.

SUMMARY

According to a first aspect of the disclosure, there is provided athin-film transistor comprising a gate, a drain, a source and a channel,which further comprises a current enhancement portion, the currentenhancement portion is provided between the drain and the source.

According to a second aspect of the disclosure, there is provided anarray substrate, which includes a display region and a non-displayregion, wherein the display region and/or the non-display region includethe thin-film transistor as described above.

According to a third aspect of the disclosure, there is provided adisplay panel which includes the array substrate as described above.

According to a fourth aspect of the disclosure, there is provided adisplay device which includes the display panel as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to illustrate the technical solutions of the embodiments of thedisclosure more clearly, drawings of the embodiments will be explainedbriefly below. It should be noted that drawings described below onlyrelate to some embodiments of the disclosure and do not limit thedisclosure. Those similar reference signs are used to indicate similarelements throughout the disclosure. In the drawings:

FIG. 1 is a structural diagram of a related thin-film transistor;

FIG. 2 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure;

FIG. 3 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure;

FIG. 4 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure;

FIG. 5 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure;

FIG. 6 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure;

FIG. 7 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure;

FIG. 8 is a diagram of a layered structure of a cross section A1-A2 ofthe thin-film transistor shown in FIG. 7;

FIG. 9 is a diagram of charge distribution when the thin-film transistorshown in FIG. 7 works;

FIG. 10 is a structural diagram of a thin-film transistor of a U shapechannel according to some embodiments of the disclosure.

DETAILED DESCRIPTION

In order to make purposes, technical solutions and advantages of theembodiments of the disclosure more clear, a clear and completedescription of technical solutions of the embodiments of the disclosurewill be given below in conjunction with drawings. Obviously, theembodiments described are a part of the embodiments of the disclosure,but not all of them. Based on the described embodiments of thedisclosure, all other embodiments obtained by those skilled in the artwithout creative labor also fall within the protection scope of thedisclosure.

FIG. 1 is a structural diagram of a related thin-film transistor. Asshown in FIG. 1, the thin-film transistor includes a substrate 1, a gate2, a gate insulation layer 3, an active layer 4, a drain 5 and a source6, a passivation layer 7 which are laminated successively. When avoltage is applied to the gate 2 to turn on the transistor, a currentflows between the drain 5 and the source 6 via the active layer 4.

If the ability of the current flowing between the drain 5 and the source6 is enhanced, the same or a higher ON current can be provided while theoccupied space of the thin-film transistor is reduced. In this way, whenthe thin-film transistor is applied in the pixel unit of the displayregion of the display device, the aperture ratio of the pixel unit canbe improved. When the thin-film transistor is applied in a circuit, suchas an anti-electrostatic circuit, in the non-display region of thedisplay device, the frame region of the display device can be reduced.

Some embodiments of the disclosure provide a thin-film transistor whichincludes a current enhancement portion, and the current enhancementportion is provided between the drain 5 and the source 6. The currentenhancement portion is used to enhance the current flowing between thedrain 5 and the source 6.

In some embodiments, the current enhancement portion may include atleast one protrusion portion, and the protrusion portion is provided onthe drain and/or the source, and faces the source and/or the drain,i.e., faces a channel between the drain and the source.

Optionally, in order to enhance the current better, the protrusionportion may include a tip.

FIG. 2 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure. As shown in FIG. 2, the currentenhancement portion of the thin-film transistor includes a protrusionportion 8 provided on the drain 5 and facing the source 6, and theprotrusion portion 8 includes one tip 9.

Since the protrusion portion 8 has a strong accumulation effect oncharges, the thin-film transistor will have larger passing current withthe same breadth length ratio. Therefore, when the thin-film transistorin these embodiments is employed, larger passing current can be providedusing smaller occupied space, and the occupied space of the thin-filmtransistor may be reduced. In this way, when the thin-film transistor isapplied to the display region, the aperture ratio of the pixel unit canbe improved. When the thin-film transistor is applied to the non-displayregion, the frame region of the display device can be reduced. The tip 9can further improve the ability of accumulating of the charges, therebyfurther reducing the occupied space, further improving the apertureratio or reducing the frame region of the display device.

Those skilled in the art can clearly understand that, in someembodiments, the current enhancement portion of the thin-film transistorincludes a protrusion portion provided on the source 6 and facing thedrain 5, and the protrusion portion includes one tip. In someembodiments, the current enhancement portion of the thin-film transistorincludes a protrusion portion on the source 6 and facing the drain 5 anda protrusion portion on the drain 5 and facing the source 6, and each ofthe protrusion portions includes one tip.

FIG. 3 is a structural diagram of a thin-film transistor of someembodiments of the disclosure. As shown in FIG. 3, the currentenhancement portion of the thin-film transistor includes a protrusionportion 8 provided at the drain 5 and a protrusion portion 8 provided atthe source 6, and the protrusion portion 8 at the drain 5 may includeone tip 9.

In FIGS. 2 and 3, the protrusion portion 8 and the tip 9 are shown as awhole, but this is not a limitation on the shape of the protrusionportion 8 and the tip 9. The protrusion portion 8 may have a shape suchas a trapezoid, a triangle, a semi-circle and so on. For example, asshown in FIG. 3, the protrusion portion 8 on the source 6 is semi-circleshaped. In a case where the tip 9 is provided on the protrusion portion8, the protrusion portion 8 may also be rectangular. As long as aprotrusion can be formed on the ends of the drain 5 or the source 6, aneffect of improving the charge accumulation ability can be achieved.

In addition, the number of the tip 9 is not limited. A plurality of tips9 may be provided on at least one of the protrusion portion 8 of thedrain 5 and the protrusion portion 8 of the source 6. The number of thetips 9 is not limited. The increase in the number of the tips 9 canguarantee that the thin-film transistor has a more stable performance.

FIG. 4 is a structural diagram of a thin-film transistor of someembodiments of the disclosure. As shown in FIG. 4, an array ofprotrusion portions 8 facing a channel (the portion between the drain 5and the source 6) are provided on the drain 5, and the protrusionportions 8 include tips 9. In some embodiments, an array of protrusionportions 8 facing a channel (the portion between the drain 5 and thesource 6) are provided on the source 6 and the protrusion portions 8include tips 9, which is not shown.

FIG. 5 is a structural diagram of a thin-film transistor of someembodiments of the disclosure. As shown in FIG. 5, an array ofprotrusion portions 8 facing the channel are provided on both the drain5 and the drain 6.

In some embodiments of the disclosure, the current enhancement portionmay include an island portion provided between the drain 5 and thesource 6, and the island portion is separate from the drain 5 and thesource 6. The island portion is located between the drain 5 and thesource 6, and can accumulate charges.

The island portion may further include at least one protrusion end, andthe at least one protrusion end faces at least one of the drain 5 andthe source 6. Even if no protrusion portion 8 is provided on the source5 and the drain 6, the island portion 10 can also improve the ability ofaccumulating charges. The protrusion end can further improve the abilityof accumulating charges, thereby further reducing the occupied space,further improving the aperture ratio or reducing the frame region of thedisplay device. The protrusion end may be a tip.

FIG. 6 is a structural diagram of a thin-film transistor according tosome embodiments of the disclosure. As shown in FIG. 6, in this example,the current enhancement portion of the thin-film transistor furtherincludes an island portion 10 provided between the drain 5 and thesource 6, and the island portion 10 is separate from the drain 5 and thesource 6. The island portion 10 includes two protrusion ends 11 facingthe drain 5 and the source 6 respectively. The protrusion ends 11 aretips.

As shown in FIG. 6, the island portion 10 including the protrusion ends11 may be integrally formed as a prism with tips, but the island portion10 may also be other shapes with or without tips. Providing the islandportion 10 in the channel may improve the current when the thin-filmtransistor is turned on.

FIG. 7 is a structural diagram a thin-film transistor of someembodiments of the disclosure. FIG. 8 is a diagram of a layeredstructure of a cross section A1-A2 of the thin-film transistor shown inFIG. 7. As shown in FIGS. 7 and 8, the current enhancement portion ofthe thin-film transistor includes an island portion 10 provided betweenthe drain 5 and the source 6, and the island portion 10 is separate fromthe drain 5 and the source 6. The island portion 10 includes twoprotrusion ends 11 which face the drain 5 and the source 6 respectively.The protrusion ends 11 are tips. The current enhancement portion of thethin-film transistor also includes a protrusion portion 8 provided atthe drain 5 and a protrusion portion 8 provided at the source 6, andeach of the protrusion portions 8 includes one tip 9.

FIG. 9 is a diagram of charge distribution when the thin-film transistorshown in FIG. 7 works. As shown in FIG. 9, the current flows from thesource 6 to the drain 5. A large number of positive charges areaccumulated at the tip 9 of the protrusion portion 8 on the source 6 towhich a comparatively high voltage is applied. Because ofinter-attraction of positive charges and negative charges, a largenumber of negative charges are accumulated on the protrusion end 11 ofthe island portion 10 facing the source 6, such that positive chargesare accumulated on the protrusion end 11 of the island portion 10 of thepointed island facing the drain 5, while negative charges areaccumulated at the tip 9 of the protrusion portion 8 on the drain 5. Inthe case of applying the same voltage to the source 6, in the thin-filmtransistor of this example, since a large number of charges areaccumulated at respective tips 9 and protrusion ends 11, it can beguaranteed that bigger current flows when the thin-film transistor is inthe ON state. The island portion 10 can increase the breadth lengthratio of the channel, improve the ability of passing the current, and inthe case of having protrusion ends 11, can further increase the currentbetween the drain 5 and the source 6.

In the embodiments described above, the protrusion portion 8 provided atthe drain 5 and the protrusion portion 8 provided at the source 6, orthe protrusion portion 8 and the protrusion end 11 of the island portion10, may be for example correspondingly arranged in a one-to-onecorresponding way, and may also not be correspondingly arranged, both ofwhich may achieve the effect of increasing the current.

Those skilled can also understand that any arrangement of the protrusionportion as described above can be applied in combination with anyarrangement of the island as described above.

FIG. 10 is a structural diagram of a thin-film transistor of a U shapechannel of some embodiments of the disclosure. As shown in FIG. 10, thecurrent enhancement portion of the thin-film transistor includes anarray of protrusion portions 8 provided at the drain 5 facing thechannel and an array of protrusion portions 8 provided at the source 6facing the channel. In the context of the thin-film transistor of the Ushape channel, the existence of the current enhancement portion canincrease the breadth length ratio of the channel more directly and moreeffectively, thereby enhancing the ability of passing the current.

In some embodiments of the disclosure, the current enhancement portionmay be made of a metal material which is the same as the drain 5 and thesource 6. For basic purposes of the disclosure, as long as internalpositive and negative charges can move and accumulate at differentsurfaces or ends when the current enhancement portion is influenced bythe electric field, it is possible to achieve accumulation of chargesand increase the ON current of the thin-film transistor. However, asviewed from simplification of the manufacturing process of the thin-filmtransistor, it is more convenient for the current enhancement portion tobe made of the same metal material as the drain 5 and the source 6. Assuch, the protrusion portion 8 and/or the island portion 10 can beformed as reserved patterns directly when forming the patterns of thedrain 5 and the source 6. As such, it is not necessary to adjust therelated manufacturing process of the thin-film transistor, and there isno increase in the production cost.

Some embodiments of the disclosure further provide an array substratewhich includes the thin-film transistor as described above. In someembodiments of the disclosure, the thin-film transistor may be includedin a display region of the array substrate. In some embodiments of thedisclosure, the thin-film transistor may also be included in anon-display region of the array substrate.

In this way, including the thin-film transistor as described above inthe pixel unit of the display region can improve the aperture ratio ofthe pixel unit. Including the thin-film transistor as described above ina circuit, such as an anti-electrostatic circuit, in the non-displayregion can reduce the frame region.

Some embodiments of the disclosure further provide a display panel whichincludes the array substrate as described above.

Some embodiments of the disclosure further provide a display devicewhich includes the display panel as described above. The display devicemay be any product or component having a display function, such as aliquid crystal panel, electronic paper, an OLED panel, a cellphone, atablet computer, a TV set, a display, a notebook computer, a digitalphoto frame, a navigator and so on.

It may be understood that the above embodiments are only exemplaryembodiments adopted to explain the principles of the disclosure, but thedisclosure is not limited thereto. For those ordinary skilled in theart, various variations and improvements may be made without departingfrom the spirits and nature of the disclosure, which are also consideredto be within the protection scope of the disclosure.

1. A thin-film transistor comprising a gate, a drain, a source and achannel, wherein the thin-film transistor further comprises a currentenhancement portion, and the current enhancement portion is providedbetween the drain and the source.
 2. The thin-film transistor accordingto claim 1, wherein the current enhancement portion includes at leastone protrusion portion, and the at least one protrusion portion isprovided on at least one of the drain or the source, and faces thechannel.
 3. The thin-film transistor according to claim 2, wherein theat least one protrusion portion is trapezoidal shaped, triangular shapedor semi-circular shaped.
 4. The thin-film transistor according to claim2, wherein the at least one protrusion portion provided on the drain andthe at least one protrusion portion provided on the source are arrangedcorrespondingly.
 5. The thin-film transistor according to claim 2,wherein the at least one protrusion portion includes a tip.
 6. Thethin-film transistor according to claim 1, wherein the currentenhancement portion includes an island portion provided between thedrain and the source, and the island portion is separate from the drainand the source.
 7. The thin-film transistor according to claim 6,wherein the island portion includes at least one protrusion end, and theat least one protrusion end faces at least one of the drain or thesource.
 8. The thin-film transistor according to claim 7, wherein thecurrent enhancement portion includes at least one protrusion portion,and the at least one protrusion portion is provided on at least one ofthe drain or the source, and faces the channel; the at least oneprotrusion end and the at least one protrusion portion are arrangedcorrespondingly.
 9. The thin-film transistor according to claim 7,wherein the at least one protrusion end is a tip.
 10. The thin-filmtransistor according to claim 1, wherein the current enhancement portionis made of a metal material which is the same as that of the drain andthe source.
 11. An array substrate comprising a display region and anon-display region, wherein at least one of the display region and/orthe non-display region include the thin-film transistor according toclaim
 1. 12. A display panel that includes the array substrate accordingto claim
 11. 13. A display device that includes the display panelaccording to claim
 12. 14. The thin-film transistor according to claim11, wherein the current enhancement portion includes at least oneprotrusion portion, and the at least one protrusion portion is providedon at least one of the drain or the source, and faces the channel. 15.The thin-film transistor according to claim 14, wherein the at least oneprotrusion portion is trapezoidal shaped, triangular shaped orsemi-circular shaped.
 16. The thin-film transistor according to claim14, wherein the at least one protrusion portion is provided on the drainand the source, and the at least one protrusion portion provided on thedrain and the at least one protrusion portion provided on the source arearranged correspondingly.
 17. The thin-film transistor according toclaim 11, wherein the current enhancement portion includes an islandportion provided between the drain and the source, and the islandportion is separate from the drain and the source.
 18. The thin-filmtransistor according to claim 17, wherein the island portion includes atleast one protrusion end, and the at least one protrusion end faces atleast one of the drain or the source.
 19. The thin-film transistoraccording to claim 18, wherein the current enhancement portion includesat least one protrusion portion, and the at least one protrusion portionis provided on at least one of the drain or the source, and faces thechannel; the at least one protrusion end and the at least one protrusionportion are arranged correspondingly.
 20. The thin-film transistoraccording to claim 18, wherein the protrusion end is a tip.